Electric meter



10.71925 1,529,522 s. WHITE 31.501331; METER Filed July 5, 1924 3 Sheets-shed 1 Q gwtmfitoc, J L. ding "haw.

Patented Mar. 10, 1925.

UNITED, STATES ROGER S. WHITE, OF WASHINGTON, DISTRICT OF COLUMBIA ELECTRIC METER.

Application filed July 5, 1924. Serial No. 724,533.

To all whom it may concern:

Be it known that ,I, ROGER S. WHITE, a citizen of the United States, residing at Washington, in the District of Columbia,

have invented certain new and useful Improvements in Electric Meters, of which the following is a specification.

This invention relates to improvements in a well known type of direct current watthour meter, known generally as the Sangamo meter. In these meters, the motor element comprises a disk armature which rotates in a chamber filled with mercury, and a damping disk is mounted upon the top of the chamber and connected to the armature shaft. The chamber is composed of a hollow block of insulating material, to the bottom of which is secured a metal pan for supporting the. mercury. These parts, with the recording train, are assembled as a unit, and are secured by screws to a ring-shaped supportingbracket which is fastened to the back wall of the meter housing. The magnet of the motor is separately supported in the housing, and the pole pieces of the magnet project into the space enclosed by the-ring and close to the underside of the mercury pan. The construction is such that the motor element cannot be removed for inspection of the mercury .chamber without removing the magnet and the supporting bracket to which the motor element is secured and without undoing certain electrical and mechanical connections, all of which amounts substantially to dismantling the meter.

In mercury meters, the oxide forming on the surface of the mercury sometimes clogs and retards the motor, and whenthat oc.- curs it is necessary to remove the motor element and inspect and clean the mercury chamber. This operation, with the standard meters of the type'referred to requires considerable time, a large part of which is occupied in removing the parts from the meter casing and replacing thesame, and in undoing and re-establishing the necessary electrical connections.

In the present invention, I have made cer tain changes in and additions to the structure of meters of the type referred to, whereby the motor element may be quickly removed or replaced in the meter casing 'without removing the supporting bracket or the magnet, or disturbing the electrical connections of the magnet, and. whereby other electrical connections can be broken or established with greater facilfity than in. the

meters as atpresent constructed In the accompanying drawing, Fig.1 1 is afront perspective view of a mercurymeter, with the front of the; casing, the, recording train and other parts removed, showing my improvements;

Fig. 2 is a similar view, showing the motor element removed from the casing; Fig. 3 is a perspective view of the, parts composing the mercury chamber, said parts being separated from one another;

Fig. 4 is a central,'vertical section through the assembled motor element; Fig. 5 is a perspective view of the main supporting bracket withthe insulating binding posts thereon;

Fig. 6 is a detail perspective view showing the supporting bracket, a part of the motorelement, and the electrical connections to the motor element as. embodied in the meters heretofore in use and, 3

Fig. 6 is a perspective view, on a smaller scale, of the bracket heretofore in use.

Referring to Figs. to 5, inclusive, of the drawing, a represents the rear part ofthe meter casing, in the upper part of which are arranged the permanent magnets 1,'between the polesof which the dampingdisk 2 revolves, and in the lower part of the casing,

and secured thereto by a screw 3, is the electromagnet 4: which forms a part of the motor of the meter. A main supporting bracket 5 is secured to the back of the meter casing by screws 6, and this-bracket supports bracket 5, as shown in Fig. 6, the horizontal part. of the bracket belng in the form of a ring. The chamber enclosed by the hollowblock 7 and pan 8 contains mercury, indicated at 11, and the armature 12 of the motor is rotatable in the mercury. The armature shaft 13 extends upwardly above the mercury chamber and carries the damping disk 2 and a worm 1.4, the latter for driving the. registering train, 1 not shown. The structure insulation and rests directly upon the shown in Fig. 4 of the drawing is the same means,are clamped .to theterininals '15? by the studs 16. According to .my1i1nprove1 mersed in the mercury.

as theistandard .form' except forthe addition of the clampingring and aslight change in the form of the pan to make it flush with the ring, and also for a change in the form and arrangement of the ears or terminals 15, through which current is carried .to and from the mercury and the armature im- In the standard form of meter, these cars are flat, horizontally arrangedlugs, as indicated at 15? in .Fiigfi, andithese lugs areprovided with ver 'tical openings through which studs16 pass,

and the terminals '17 ,ofthe seriescoil of the [motor .magnet and the flatbands 18, which lead [to and support thelight load adjusting ments, as shownain Fig. hgtheears or-terminals 15 have horizontal openings 19,. in which are fitted tubes 20, .igs. 1;, 2, and 3) adapted ,to .pass .on to studs .orbinding ,posts 21 whiclrare supported by blocksof insulatingmaterialj22, which aresecured :to the top ofthe'bracket 5. The terminals 17 of the .seriescoilflof ,themotor magnet also,.in accordance with my improvements,1fit over-the studs 21 and against the .insuIatingbl cks 22, ;and when the motor selementis in:posi- .tion upon the bracket, the tubes .20 bear against these terminals. The bands 18, which support, the light load adjusting 1 means, are also formedandperforated soas I to fit on tothe binding posts 2land against the outer ends of the :tubes 20, and clamping .nuts23, threaded on to the endsof .thebind .ing posts, clamp the several parts of the poststogether. r

In the meters ofthis type as ordinarily constructed, the horizontal portion of the bracket .5 'is int-he form of a ring'and the motor element is securely fastened to this ring'fby a number of screws 24, (Fig. 6)

spacedv suitable distances apart about the ring. These screws passthrough the flange 7 of. themercury :cha-m'ber. With this construction, in .themeters ofstandard make, it is impossible to remove .the motor element 1 withoutremoving the bracket. Also, in the standard form of meter, the magnet poles project into the space enclosed by the ring on the shelf andv are. interlocked with .th shelf, so that it is impossible to remove the shelf and motor element without also re- 1 moving themotor magnet after undoing its electrical connections.

According .to -my improvements, it is unnecessary to secure the motor element to the bracket or shelf by screws, because the studs 21, passing through the tubes of the terminals15, hold-the motor element in its proper position over the magnet and the motor element therefore simply .restsupon the shelf Without being directly secured thereto. Preferably, although {not necessarily, the front half of, thering of "the bracket or shelf is armature is on the bracket.

removed, leaving only a semircircular part, as shown in Figs. 1, 2, 3, and 5. p

7 With this modified construction of the standard form of meter, it will be evident "thatthe motor element may be removed in .a fewvmoments by loosening the nuts '23 and sliding the motor element forward on the rods2l. As will be plain from Fig. 2, the I motor magnet and its connections are not disturbed. by removing the motor element. .It will also be evident that the motor Qelement can be replaced in its projperposition and the connections made :by sliding the =f ele-' mentibackward on the shelf and .causingthe tubes on the armature terminals :to .pa-ss on to the rods 21.. When the bands 18 are -ap' plied .to .the gtfront-ends .oifithe .rods and the nuts are tightened, all of theelectrical 1coni nections will be reestablished ancbt-he motor element will be securely held in its proper position. 7 t I If desired, the supporting bracket may be omittedand the motor element .will then be entirely supported by the rods 2: 1,,..fittingwithinthetubes or sleeves 20, In that event,

the insulating supports ,forthe posts would,

ing insteadlof thebracketi WhatI claim is:

1. In a meterof the .typedescribed, a\casing, a horizontally arranged bracketsecured within the casing, {a motor element, having armature terminals projecting from its sides, slidabl y mounted on vthebnacket,p and stationary insulated terminals adapted .to .be engaged by said armature-terminals when the 2. In a meterof the typedescribed, acasing, a horizontally arranged bracket secured within the casing, a motor element, having armature terminals projecting from itssides,

of course, be secured tothe backof-the .cas-

slidably mounted on the bracket, and sta tionary insulated binding posts adapted to be vengagedby said armatureterminalsv when the armature is on the bracket.

s 3. In a meterof the type described, a casing, a horizontally arranged bracketsecured within the casing, amotor-element slidably mounted on'thebracket, said elementhaving 5- I m e th w-P "eras ing, a horizontally arranged bracket secured therein, insulated binding posts extending horizontally adjacent the bracket, a motor element having a mercury chamber, said chamber comprising a hollow member of insulating material, a metal pan fitting against the under side of said member, and a clamping ring securing said pan to said member and substantially flush with the bottom of the pan, said ring adapted to slidingly engage and rest upon the bracketand said element having terminals adapted to engage said binding posts when the element is slid on to the bracket.

6. In a meter of the type described, a cas- 7 ing, stationary insulated binding posts extendinghorizontally in said casing, and a motor element having armature terminals projecting from its sides, said terminals adapted to slidingly engage said posts.

In testimony whereof I hereunto affix my signature.

4 nosna s. WHITE, 

